Pei X
Department of Experimental Hematology, Beijing Institute of Radiation Medicine, People's Republic of China.
Int J Hematol. 1999 Dec;70(4):213-5.
Hematopoietic stem cells (HSC) possess multipotentiality, enabling them to self-renew and also to produce mature blood cells, such as erythrocytes, leukocytes, platelets, and lymphocytes. CD34 is a marker of human HSC, and all colony-forming activity of human bone marrow (BM) cells is found in the CD34+ fraction. Clinical transplantation studies that used enriched CD34+ BM cells indicated the presence of HSC with long-term BM reconstitutional ability within this fraction. But recent studies in NOD/SCID mice, rhesus monkeys, and human/sheep competitive engraftment models have provided evidence for the presence of a rare cell population that contains progenitors capable of producing CD34+ cells in vitro. These progenitors are highly enriched in HSC and have competitive long-term in vivo repopulating potential devoid of both CD34 and lineage-marker expression. These new findings add to the growing evidence that some stem cells in the BM do not express the CD34 marker, which is currently used to select stem cells for transplantation.
造血干细胞（HSC）具有多能性，使其能够自我更新并产生成熟血细胞，如红细胞、白细胞、血小板和淋巴细胞。CD34是人类造血干细胞的标志物，人类骨髓（BM）细胞的所有集落形成活性都存在于CD34+部分中。使用富集的CD34+骨髓细胞进行的临床移植研究表明，该部分中存在具有长期骨髓重建能力的造血干细胞。但最近在NOD/SCID小鼠、恒河猴以及人类/绵羊竞争性植入模型中的研究提供了证据，证明存在一种罕见细胞群体，其中含有能够在体外产生CD34+细胞的祖细胞。这些祖细胞在造血干细胞中高度富集，具有竞争性的长期体内再植潜力，且不表达CD34和谱系标志物。这些新发现进一步证明，骨髓中的一些干细胞不表达目前用于选择移植干细胞的CD34标志物。
